{"schema":"threatline.record/2","record":{"id":"CVE-2026-55787","aliases":["GHSA-794r-5rp2-fpg8","PYSEC-2026-2481"],"summary":"Flyto2 Core: SSRF guard bypass via IPv6 transition addresses (IPv4-mapped / 6to4 / NAT64) in validate_url_ssrf","details":"Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.3, validate_url_ssrf and is_private_ip in src/core/utils.py compare resolved addresses only against native private IPv4 and IPv6 ranges and do not unwrap IPv4-mapped, IPv4-compatible, 6to4, or NAT64 transition addresses. An authenticated workflow author can provide a transition-form literal URL through the Execution API POST /v1/execute route, http.get, or sibling guarded outbound-request modules, causing the guard to accept an address whose embedded IPv4 points to loopback, RFC 1918, or cloud metadata services. On a host that routes the selected transition form, the outbound request reaches the internal destination and returns the response body to the workflow caller, enabling read SSRF and disclosure of internal-service data or cloud credentials. This issue is fixed in version 2.26.3.","categories":["Libraries & packages"],"product":"flyto-core","vendor":"flytohub","ecosystem":"PyPI","affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-55787","source_modified_at":"2026-10-15T14:55:23.673Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"flyto-core","vendor":"flytohub","versions":[{"version":"< 2.26.3","status":"affected"}],"defaultStatus":null},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-794r-5rp2-fpg8","source_modified_at":"2026-07-13T16:42:32.624171385Z","fetched_at":"2026-10-23T18:48:36.087640Z","package":{"name":"flyto-core","ecosystem":"PyPI","purl":"pkg:pypi/flyto-core"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.26.3"}]}],"versions":["1.0.0","1.0.1","1.0.2","1.0.3","1.0.4","1.0.5","1.0.6","1.0.7","1.0.8","1.0.9","1.1.0","1.1.1","1.11.0","1.12.0","1.13.0","1.14.0","1.14.1","1.14.2","1.15.0","1.16.0","1.16.1","1.16.10","1.16.2","1.16.3","1.16.4","1.16.5","1.16.6","1.16.7","1.16.8","1.16.9","1.2.0","1.3.0","1.4.0","1.5.0","1.5.1","1.5.2","1.5.4","1.6.0","1.6.1","1.6.2","1.6.3","1.6.4","1.6.5","1.7.0","1.7.1","1.7.2","1.7.3","1.7.4","1.7.5","1.7.6"]}],"fixed_versions":[{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-794r-5rp2-fpg8","source_modified_at":"2026-07-13T16:42:32.624171385Z","fetched_at":"2026-10-23T18:48:36.087640Z","package":{"name":"flyto-core","ecosystem":"PyPI","purl":"pkg:pypi/flyto-core"},"version":"2.26.3"}],"cvss":7.1,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00236,"percentile":0.13731,"score_date":"2026-10-23"},"published_at":"2026-10-14T18:13:52.454Z","modified_at":"2026-10-15T14:55:23.673Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-55787","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-15T14:55:23.673Z"},{"source":"OSV","url":"https://osv.dev/vulnerability/GHSA-794r-5rp2-fpg8","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-07-13T16:42:32.624171385Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-55787","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","OSV","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/flytohub/flyto-core/security/advisories/GHSA-794r-5rp2-fpg8","tags":["exploit"]},{"source":"CVE List","url":"https://github.com/flytohub/flyto-core/pull/20","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/flytohub/flyto-core/commit/519e040384a74984848c4e84a6600e5f1020a6d2","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/flytohub/flyto-core/releases/tag/v2.26.3","tags":["x_refsource_MISC"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"poc","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-15T14:54:19.186468Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"ecosystem","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-15T14:55:23.673Z","content_hash":"ec13e18a3f5afba8d11c0a767e30d2ff6bb9754a71402daeebda47b8a842d642"}}